Matt,
To clarify:
Bob's quote - (and your reprint of it) - states that the signal reaching the DRIVER in the sub in not the same as the signal reaching the drivers in your main speakers. Assuming that you are using a powered sub, he is correct. The input signal routed by the speaker level REL connector to the sub goes first to the sub's internal amp and the output from that internal amp goes to the driver in the subwoofer.
If you're using a passive subwoofer and not bi-amping, then the drivers in both subwoofer and mains would see the same signal. The trade-offs in doing that are significant.
Some folks prefer the REL speaker level arrangement and claim that "capturing" the characteristics of the main amp in the input signal for the subwoofer amp has benefits (and I won't argue that one way or the other), but that's not the same as saying that all the drivers see the same signal with this set-up.
To clarify:
Bob's quote - (and your reprint of it) - states that the signal reaching the DRIVER in the sub in not the same as the signal reaching the drivers in your main speakers. Assuming that you are using a powered sub, he is correct. The input signal routed by the speaker level REL connector to the sub goes first to the sub's internal amp and the output from that internal amp goes to the driver in the subwoofer.
If you're using a passive subwoofer and not bi-amping, then the drivers in both subwoofer and mains would see the same signal. The trade-offs in doing that are significant.
Some folks prefer the REL speaker level arrangement and claim that "capturing" the characteristics of the main amp in the input signal for the subwoofer amp has benefits (and I won't argue that one way or the other), but that's not the same as saying that all the drivers see the same signal with this set-up.